I frequently deal with 3D data and would like to sum (or find the
mean, etc.) over the last two axes. I.e. sum a[i,j,k] over j and k.
I find using .sum() really convenient for 2d arrays but end up
reshaping 2d arrays to do this. I know there has to be a more
convenient way. Here's what I'm doing
a = np.arange(27).reshape(3,3,3)
# sum over axis 1 and 2
result = a.reshape((a.shape[0], a.shape[1]*a.shape[2])).sum(axis=1)
Is there a cleaner way to do this? I'm sure I'm missing something obvious.
Thanks,
Greg